Keep the keyboard opened on configuration changed

rich-html-editor/src/main/java/com/infomaniak/lib/richhtmleditor/Extensions.kt

@@ -1,6 +1,9 @@
 package com.infomaniak.lib.richhtmleditor
 
 import android.content.Context
+import android.os.Build
+import android.os.Bundle
+import android.view.AbsSavedState
 import android.webkit.WebView
 import java.io.BufferedReader
 
@@ -33,3 +36,11 @@ internal fun WebView.injectCss(css: String) {
 
     evaluateJavascript(addCssJs, null)
 }
+
+fun Bundle.getParcelableCompat(key: String, clazz: Class<AbsSavedState>): AbsSavedState? {
+    return if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.TIRAMISU) {
+        getParcelable(key, clazz)
+    } else {
+        getParcelable(key)
+    }
+}

rich-html-editor/src/main/java/com/infomaniak/lib/richhtmleditor/RichHtmlEditorWebView.kt

@@ -3,10 +3,14 @@ package com.infomaniak.lib.richhtmleditor
 import android.annotation.SuppressLint
 import android.content.Context
 import android.graphics.Rect
+import android.os.Bundle
+import android.os.Parcelable
 import android.util.AttributeSet
+import android.view.AbsSavedState
 import android.view.ViewGroup
 import android.webkit.WebView
 import android.webkit.WebViewClient
+import androidx.core.os.bundleOf
 import androidx.core.view.updateLayoutParams
 import com.infomaniak.lib.richhtmleditor.executor.JsExecutableMethod
 import com.infomaniak.lib.richhtmleditor.executor.JsExecutor
@@ -38,6 +42,8 @@ class RichHtmlEditorWebView @JvmOverloads constructor(
     defStyleAttr: Int = 0,
 ) : WebView(context, attrs, defStyleAttr) {
 
+    private var keepKeyboardOpenedOnConfigurationChanged: Boolean = false
+
     private val documentInitializer = DocumentInitializer()
     private val jsExecutor = JsExecutor(this)
     private val scriptCssInjector = ScriptCssInjector(this)
@@ -135,6 +141,7 @@ class RichHtmlEditorWebView @JvmOverloads constructor(
     }
 
     fun requestFocusAndOpenKeyboard() {
+        keepKeyboardOpenedOnConfigurationChanged = true
         keyboardOpener.executeWhenDomIsLoaded(Unit)
     }
 
@@ -143,13 +150,32 @@ class RichHtmlEditorWebView @JvmOverloads constructor(
         jsExecutor.executeWhenDomIsLoaded(JsExecutableMethod("exportHtml"))
     }
 
+    override fun onSaveInstanceState(): Parcelable {
+        val superState = super.onSaveInstanceState()
+        return bundleOf(
+            KEYBOARD_SHOULD_REOPEN_KEY to keepKeyboardOpenedOnConfigurationChanged,
+            SUPER_STATE_KEY to superState,
+        )
+    }
+
+    override fun onRestoreInstanceState(state: Parcelable?) {
+        (state as Bundle?)?.getBoolean(KEYBOARD_SHOULD_REOPEN_KEY)?.let { keepKeyboardOpenedOnConfigurationChanged = it }
+        super.onRestoreInstanceState(state?.getParcelableCompat(SUPER_STATE_KEY, AbsSavedState::class.java))
+    }
+
     override fun onFocusChanged(focused: Boolean, direction: Int, previouslyFocusedRect: Rect?) {
         super.onFocusChanged(focused, direction, previouslyFocusedRect)
-        if (focused) jsExecutor.executeWhenDomIsLoaded(JsExecutableMethod("requestFocus"))
+        if (focused) {
+            jsExecutor.executeWhenDomIsLoaded(JsExecutableMethod("requestFocus"))
+            if (keepKeyboardOpenedOnConfigurationChanged) keyboardOpener.executeWhenDomIsLoaded(Unit)
+        } else {
+            keepKeyboardOpenedOnConfigurationChanged = false
+        }
     }
 
     override fun onDetachedFromWindow() {
         super.onDetachedFromWindow()
+        keyboardOpener.removePendingListener()
         jsBridgeJob.cancel()
     }
 
@@ -206,4 +232,9 @@ class RichHtmlEditorWebView @JvmOverloads constructor(
     private fun unsupported() {
         throw UnsupportedOperationException("Use setHtml() instead")
     }
+
+    companion object {
+        private const val KEYBOARD_SHOULD_REOPEN_KEY = "keyboardShouldReopen"
+        private const val SUPER_STATE_KEY = "superState"
+    }
 }

rich-html-editor/src/main/java/com/infomaniak/lib/richhtmleditor/executor/KeyboardOpener.kt

@@ -2,13 +2,42 @@ package com.infomaniak.lib.richhtmleditor.executor
 
 import android.app.Activity
 import android.view.View
+import android.view.ViewTreeObserver
 import android.view.inputmethod.InputMethodManager
 
 internal class KeyboardOpener(private val view: View) : JsLifecycleAwareExecutor<Unit>() {
+
+    private var listener: ViewTreeObserver.OnWindowFocusChangeListener? = null
+
     override fun executeImmediately(value: Unit) {
         if (view.requestFocus()) {
-            val inputMethodManager = view.context.getSystemService(Activity.INPUT_METHOD_SERVICE) as InputMethodManager
-            inputMethodManager.showSoftInput(view, InputMethodManager.SHOW_IMPLICIT)
+            if (view.hasWindowFocus()) {
+                openKeyboard()
+            } else {
+                // The window won't have the focus most of the time when the configuration changes and we want to reopen the
+                // keyboard right away. When this happen, we need to wait for the window to get the focus before opening the
+                // keyboard.
+                listener = object : ViewTreeObserver.OnWindowFocusChangeListener {
+                    override fun onWindowFocusChanged(hasFocus: Boolean) {
+                        if (hasFocus) {
+                            openKeyboard()
+                            view.viewTreeObserver.removeOnWindowFocusChangeListener(this)
+                        }
+                    }
+                }
+
+                view.viewTreeObserver.addOnWindowFocusChangeListener(listener)
+            }
         }
     }
+
+    fun removePendingListener() {
+        view.viewTreeObserver.removeOnWindowFocusChangeListener(listener)
+        listener = null
+    }
+
+    private fun openKeyboard() {
+        val inputMethodManager = view.context.getSystemService(Activity.INPUT_METHOD_SERVICE) as InputMethodManager
+        inputMethodManager.showSoftInput(view, InputMethodManager.SHOW_IMPLICIT)
+    }
 }